1. Technical Field
The present invention relates to a fast Fourier transform method and an inverse fast Fourier transform method which conventionally use 2n (2 to the nth power) points and are incapable of an FFT using other specified number of points.
2. Prior Art
A conventional fast Fourier transform (FFT) has a restriction that the number of points N must be N=2n. Otherwise, it has been impossible to perform a fast operation of discrete Fourier transform (DFT) by using an existing apparatus.